Modular printing unit

ABSTRACT

In order to provide a printing unit ( 1; 50 ) of modular design with the lowest possible expenditure on construction and high flexibility, the printing unit ( 1; 50 ) of modular design for printing webs ( 29 ) has a stand ( 2; 2′; 54 ), which is provided with at least one crossmember ( 3; 4; 51 ) at both ends (drive and operating side), printing cylinders ( 9  to  16 ) being mounted in the crossmembers ( 3; 4; 51 ) in such a way that a structural unit comprising crossmembers ( 3; 4; 51 ) and printing cylinders ( 9  to  16 ) can be taken completely out of and put into the stand ( 2; 2′; 54 ).

PRIORITY CLAIM

This is a U.S. national stage of application No. PCT/EP2003/014208,filed on 13 Dec. 2003. Priority is claimed on the followingapplication(s): Country: Germany, Application No.: 102 60 574.2, Filed:21 Dec. 2002.

BACKGROUND OF THE INVENTION

The invention relates to a printing unit for printing webs.

The object of the invention is to provide a printing unit which isdesigned with the lowest possible expenditure on construction and highflexibility.

SUMMARY OF THE INVENTION

The modular printing unit according to the invention comprises threemain groups a frame; subunits; and at least one cross member:

-   -   the frame, performs the load-bearing function and accommodates        all the services and operating elements (alternatively a stand        configured in the manner of a frame can also be used),    -   the format-independent “subunits” are mounted in the frame or        stand and which contain the auxiliary subassemblies necessary to        the printing process (In the offset process which is common        nowadays, the subunits mainly include inking and damping units),        and    -   the at least one crossmember is configured as a “locking bar”,        which is arranged in the frame or connected to the stand on both        sides and in which the main subassemblies necessary for        printing—plate cylinders and rubber-covered cylinders in offset        printing—are mounted.        In addition, additional equipment such as plate loading systems        or digital imaging systems (direct imaging) can be mounted in        the crossmember.

Each crossmember is equipped with one or more swinging arms for what areknown as the printing mechanisms, in order to pivot the rubber-coveredcylinders.

A great advantage of this system is the independence of the printingprocess, so that adaptations to the future innovations are possible atany time by replacing the corresponding subassemblies. In addition, thefundamental change or adaptation to other printing processes and to allvarieties of offset printing can be covered. By means of the appropriateadaptation of the subunits and/or the crossmember, the printing unit canbe extended or converted to anilox, dry offset printing, gravureprinting or any printing process developed in the future, with itspreconditions.

The modular printing unit of the present invention may be configured asan H printing unit equipped with 1, 2, 3, 4 or more printing points or amodular printing unit configured as an I printing unit with 1, 2 or moreprinting points. In the I design, imprinting mechanisms may also beinstalled. The subunits of the modular printing unit are preassembledfor this purpose and are attached to the frame.

The ratio of the plate cylinders to rubber-covered cylinders mounted inthe crossmember can be x:x or x:y (for y>x), but advantageously 1:1, 1:2and 2:2. However, 2:3, 3:3 and so on are just as conceivable.

The proportion of the wall for inking and damping units is separate fromthe proportion of the wall for plate cylinders and rubber-coveredcylinders and is called a “subunit” here. The inking units canalternatively contain 1, 2, 3 or 4 and more ink applicator rolls and asmany distributor cylinders as desired. The damping units canalternatively contain 1 or 2 damping solution transfer rolls and as manydistributor cylinders as desired. Inking and damping units can also beconnected to one or more “coupling rolls” for indirect damping.

The rubber-covered cylinder is pivoted out by means of a swinging armarranged in the crossmember for good accessibility (for examplereplacement of the rubber-covered cylinder cover, removal of a wrap);the pivot for this purpose is advantageously located at the center ofthe plate cylinder. Translational movements are not absolutely necessarybut there is the possibility of displacing the impression cylinder,rubber-covered cylinder and plate cylinder arranged in the crossmemberin the translational direction in relation to one another.

The subunits are designed in a modular way, which are advantageouslyconstructed identically, these primarily accommodating inking anddamping units. As a result of the identical structure of the subunits,these can advantageously be given the same dimensions, which improvesthe replaceability and minimizes the production costs.

From this, in the case of identical subunits, it is possible to derive

-   -   a) H printing units with identical height and, if appropriate,        format-dependent different width with a horizontal crossmember        and    -   b) I printing units with identical widths and, if appropriate,        format-dependent different height with vertical crossmember.

By means of the combination of a top left and bottom right subunitdesigned in a modular way, it is possible to construct an I printingunit for a left-right machine; by means of the combination of a topright and bottom left subunit designed in a modular way, it is possibleto construct an I printing unit for a right-left machine.

The plate cylinders and rubber-covered cylinders may be arranged in thecrossmember in one line parallel to the crossmember, crossed in anydirection or arranged at angles to one another.

The modular printing unit can be equipped with various types of drive:

-   -   an H drive for the simultaneous drive of four printing        mechanisms, integrated in the frame;    -   a bridge drive for the simultaneous drive of two printing        mechanisms, integrated in the crossmember, advantageously        positioned at the center of the plate cylinder and driving the        rubber-covered cylinder via drive elements; or    -   an individual drive for each printing mechanism, integrated in        the crossmember, advantageously positioned at the center of the        plate cylinder and driving the rubber-covered cylinder via drive        elements, or integrated in the respective subunit.

In order to throw the print on and off, plate cylinder andrubber-covered cylinder can be moved toward each other via eccentrics.

The frames, crossmembers and swinging arms can be createdconstructionally simply and, as a result, cost-effectively. For example,the crossmembers can be implemented with commercially availableprofiles. In addition, the printing units configured by means of theframe, the crossmembers and the swinging arms are distinguished by areduced-weight, compact and space-saving design.

Thus, using one and the same printing unit, it is possible to print asdesired in the gravure printing or offset printing process, it beingpossible for the machine to be converted simply from one process to theother as a result of the modular design and the replacement of thecrossmember fitted with the appropriate cylinders and the replacement ofthe corresponding modular subunits. In addition, both printing processescan be used simultaneously. Furthermore, for example the one printingprocess can be used for the recto printing and the other printingprocess can be used for the verso printing. The press manufacturer cancreate the machines for both processes identically from the samecomponents, which permits cost-effective fabrication. In addition, theprinting devices can be designed with variable format, that is to saythey can be converted simply to other formats, i.e. other diameters ofthe printing mechanism cylinders and section lengths. Moreover, theprinting unit can be changed over quickly to different productionvariants. Furthermore, the printing unit can also be converted to avarnishing unit or at least as a varnishing mechanism for recto printingor for verso printing.

It is significant that a printing unit of modular design is provided forprinting webs, which has a stand which is provided with at least onecrossmember at both ends (drive side and operating side), printingcylinders being mounted in the crossmembers in such a way that astructural unit comprising crossmembers and printing cylinders can betaken completely out of and put into the stand.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, wherein like reference characters denote similarelements throughout the several views:

FIG. 1 is a schematic side view of a printing unit according to theinvention, configured as an H printing unit having four printing points,

FIG. 2 is a sectional plan view of a drive of a printing mechanismaccording to FIG. 1,

FIG. 3 is a sectional plan view of a further drive of a printingmechanism according to FIG. 1,

FIGS. 4 a and 4 b are side views of a printing unit according to theinvention configured as an I printing unit,

FIGS. 5 a and 5 b are schematic side views of shows the subunits inprinting machines having different formats.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a printing unit 1 of a web-fed rotary press, comprising astand 2 constructed in the manner of a frame. Two crossmembers 3; 4 areconnected to the latter on both sides (only one side is shown in FIG.1), in each case two printing mechanisms 5 to 8 having plate cylinders 9to 12 and rubber-covered cylinders 13 to 16 being arranged in thecrossmembers 3; 4 and the crossmembers 3; 4 being arranged horizontallyin the stand 2. The plate cylinders 9 to 12 and the rubber-coveredcylinders 13 to 16 are here arranged in line in the crossmember 3; 4.They can be arranged in the crossmember 3; 4 crossed in any direction orat angles to one another, not illustrated here. Each printing mechanism5 to 8 or each plate cylinder 9 to 12 is connected to a subunit 17 to 20of modular design, the subunit 17 to 20 being arranged between therespective crossmember 3; 4 and the stand 2. Inking and damping units,not specifically illustrated, are integrated in the subunits 17 to 20.

The printing unit 1 equipped with four printing mechanisms 5 to 8 inthis way represents what is known as an H printing unit with fourprinting points. A web 29 to be printed is led through between therubber-covered cylinders 13 to 16. The printing mechanisms 5 to 8 printthe web 29 on both sides.

The rubber-covered cylinder 13; to 16 can be configured as an impressioncylinder 50, the respective form cylinder 9 to 12 belonging to therubber-covered cylinder 13 to 16 now designed as an impression cylinder42 being omitted. When impression cylinder 50 is used, the web 29 isthus printed on one side.

The respective rubber-covered cylinder 13 to 16 can be pivoted on thecrossmember 3; 4 by means of a swinging arm 21 to 24, the pivot of theswinging arm 21 to 24 preferably being an axle 25 to 28 of therespective plate cylinder 9 to 12. The crossmember 3; 4 is screwed tothe stand 2 on both sides (not specifically illustrated), so that, forexample, replacement of the respective printing mechanisms 5 to 8 can beeffected quickly.

The crossmember 3; 4 consists, for example, of sheet metal turned overat the edge or sheet metal profiles. The printing cylinders 9 to 16 canbe moved in relation to each other via bearing points configured aseccentrics in order to throw the print on/off.

FIG. 2 shows a drive 30 of the printing mechanism 5. The drive 30comprises a drive motor 31 which has a drive connection to the platecylinder 9 via a clutch 32. The plate cylinder 9 is connected to therubber-covered cylinder 13 via gears 33; 34 arranged on their axles 25;35. The drive motor 31 is arranged on a bracket 36 connected to thecrossmember 3. Mounted on the axle 25 of the plate cylinder 9 is theswinging arm 21, which can be pivoted about the axle 25 by means of apivoting motor 38 which is fixed to the bracket 36 and engages with atoothed segment 37 arranged on the winging arm 21. Before the pivotingaction, a locking device 39 has to be released which, during printingoperation, connects the swinging arm 21 to the bracket 36 in a lockingmanner. It is self-evident that the crossmember 3 is equipped with acutout 40 along the pivoting travel of the axle 35 of the rubber-coveredcylinder 13. Although not specifically illustrated, the swinging arm 21can also be pivoted by means of an operating cylinder operated bypressure medium instead of by means of the pivoting motor.

FIG. 3 shows a variant of FIG. 2. Here, the drive motor 31 drives therubber-covered cylinder 13 for example via a drive element 41, forexample a toothed belt. In a manner analogous to FIG. 2, the drive motor31 is located in its position at the center M_(p) of the plate cylinder9, in order that it does not change its position when the rubber-coveredcylinder 13 is pivoted out.

FIGS. 4A and 4B a printing unit 50 which is configured as an I printingunit. In an I printing unit 50, the crossmember 51 is, for example,configured in the shape of a T and the web 29 is led through theprinting unit 50 in the horizontal direction. The I printing unit 50 canbe equipped with 1 or 2 printing points. Thus, imprinting mechanisms canalso be incorporated in an I design. The subunits 52; 53 arepreassembled in a way analogous to FIG. 1 for this purpose and arefitted in the stand 54.

By means of the combination of a top left 52 and bottom right subunit 53designed in a modular way, it is possible to construct an I printingunit 50 for a left-right machine (see FIG. 4A); by means of thecombination of a top right 55 and bottom left subunit 56 designed in amodular way, it is possible to construct an I printing unit 50 for aright-left machine (see FIG. 4B).

The subunits 17 to 20 are shown in FIGS. 5A and 5B are arranged in twodifferent stands 2; 2′. The subunits 17 to 20 always have the samedimensions, it being possible for the stands 2; 2′ to be different intheir format or in their dimensions, the dimension and the format of thestands 2; 2′ depending on the number and dimension of the printingcylinders used. While viewing the two illustrations shown in FIGS. 5Aand 5B, it is possible to see the identically dimensioned subunits 17 to20, but with the format difference between the stands 2; 2′ representedby ΔB in FIG. 5B.

1. A printing unit of modular design for printing webs, comprising: astand having a drive side and an operating side; at least onecrossmember arranged at each of said sides of said stand, wherein saidcrossmembers are aligned horizontally or vertically; printing cylindersmounted in the crossmembers and forming a structural unit of saidprinting unit with said crossmembers such that said structural unitcomprising said printing cylinders mounted on said crossmembers isremovably received in said stand of said printing unit; and subunitscomprising auxiliary subassemblies necessary for the printing process,said subunits being replaceably arranged between said crossmember andsaid stand, and abutting a respective plate cylinder of said printingcylinders, said auxiliary subassemblies including damping and inkingunits.
 2. A printing unit of modular design for printing webs,comprising: a stand having a drive side and an operating side; at leastone crossmember arranged at each of said sides of said stand, whereinsaid crossmembers are aligned horizontally or vertically; printingcylinders mounted in the crossmembers and forming a structural unit ofsaid printing unit with said crossmembers such that said structural unitcomprising said printing cylinders mounted on said crossmembers isremovably received in said stand of said printing unit, wherein saidprinting cylinders comprise rubber cylinders arranged for printing onone or both sides of the web running therebetween and one of saidrubber-covered cylinders is mounted in a swinging arm for pivoting,wherein said swinging arm is pivotable about an axis of a plate cylinderassociated with said one of said rubber-covered cylinders.